OHE M3 PULP •
The only soft connective tissue of the tooth that occupies the center space of the tooth that contains nerves. Vessels and lymph
PULP CAVITY • Wall is made up of dentin •
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Center space housing the pulpal tissue
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Connects the orifices
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Dark line on the floor of the pulp chamber that serves as guide to locate orifices
C DENTAL FIBERS/UNMYELINATED FIBERS
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Dental papilla initiates tooth formation from odontogenesis
ODONTOBLASTIC ZONE o
Zone of the pulp tissue immediately after dentin
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Most peripheral
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For dentin formation
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Many complex junction occur between adjacent odontoblasts
FORMATIVE o
Primary function of pulp tissue
Gap junctions
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Synthesize and secrete organic matrix
Zonulae occludentes
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Transport inorganic components to newly formed matrix
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Creates an environment that permits mineralization of matrix
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Contains a lot of blood vessels
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DENTINAL TUBULES
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Hydration
DEFENSIVE o
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Changes in the shape
Formation of secondary and tertiary dentin
Junctions permit the free interchange of ions and small molecules
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Devoid of cells but in fibrous appearance
o
PLEXUS OF RACKSHOW
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Network of myelinated nerve fibers in the parietal area beneath the zone of Weil
REMAK’S FIBERS
INFLAMMATORY REACTION
Demosomes
CELL – FREE ZONE
MORPHOLOGIC
Tight junctions
Zonulae adherentes •
NUTRITIVE
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Slow, dull, more diffuse
STRUCTURAL COMPONENTS OF PULP: 4 DISTINCT ZONES
INDUCTIVE o
Fast, sharp, severe
o
FUNCTION OF PULP TISSUE: •
Sharp pain, pulsating pain, dull pain
Associated with hypersensitivity
Accessory root canal found at the furcation area of the root
DENTAL MAP
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o
FURCATION CANAL •
Inflammation of pulp
A DENTAL FIBERS/MYELINATED FIBERS
Tributaries of vessels found at the apical portion of tooth
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SENSORY
APICAL DELTA •
PULPITIS
Plexuses of non-myelinated nerve fibers along the zone of Weil
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o
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SUBODOONTOBLASTIC PLEXUSES OF NERVES
Replace odontoblasts which produces ATUBULAR DENTIN
Plexuses of non-myelinated nerve fibers along the zone of Weils and in between odontoblasts
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For mobilization and replacement of
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Capable of maturing into macrophages or assuming the function of fibroblasts and odontoblasts
PERICYTES/ROUGET’S CELLS
odontoblasts o •
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CELL – RICH ZONE o
Numerous densely packed bipolar cells with spindle shaped nuclei
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Some are fibroblasts and others are unmyelinated mesenchymal cells
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Continuous with the central portion of the pulp in both the crown and the root
IMMUNOCOMPETENT CELLS OF THE PULP: •
PULP CORE/PULP PROPER
o
Characterized by the principal cells of the pulp, immunocompetent cells, major vessels & nerves of pulp
PRINCIPAL CELLS OF THE PULP •
ODONTOBLASTS o
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Read odontoblastic zone
FIBROBLASTS o
Formative cells
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Most abundant cells
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Most common cell type of the pulp
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Numerous in the coronal potion of the pulp
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where they form the cell-rich zone o
Form and maintain the pulp matrix
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PULP MATRIX
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MACROPHAGES/HISTOCYTES o
Near blood vessels but not attaching
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Eliminates dead cells
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Presence indicates the turnover in dental pulp
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Removes bacteria and interacts with other inflammatory cells
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Presents antigen to lymphocytes
DENDRITIC CELLS o
Peripherally located
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Capture and presents foreign antigen to Tcells
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Non-phagocytic and participates in pulpal immunosurveillance
LYMPHOCYTES o
Monoclonal antibody labeling of normal dental pulp indicates there are various subgroups of T-lymphocytes associated with immune defense system
o
B-lymphocytes are not usually found in normal dental pulp
Consists of collagen and ground substance
Capable of ingesting and degrading collagen when appropriately stimulated
COLLAGEN FIBERS
UNDIFFERENTIATED MESENCHYMAL CELLS o
Reserve cells
o
Found throughout the cell-rich zone and the pulp core
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Often related to blood vessels
Contractile cells capable of reducing the size of the vessel lumen
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Principally type I and III in an approximate ration of 55:45
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TYPE Z or DENTIN COLLAGEN o
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Exclusive product of ondontoblasts
Greatest concentration is generally seen in the most apical portion of the pulp
VASCULAR SUPPLY OF PULP •
CLINICAL IMPLICATIONS:
SUPERIOR AND INFERIOR ALVEOLAR ARTERIES AND VEINS
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Pulp horns can present a potential problem in pulp exposure
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Accessory canals are important
NERVE SUPPLY OF PULP •
RACKSHOW’S PLEXUS
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MAXILLARY & MANDIBULAR BRANCHES OF TRIGEMINAL NERVE (CN V) o
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SENSORY INNERVATION
SUPERIOR CERVICAL GANGLION o
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Cementum becomes deposited around the apical canal causing cemental constrictions of apices
SYMPATHETIC INNERVATION
Thin walls of the veins are the first structures impinged
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Vascular congestion occurs leading to pulpal necrosis
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Brought about by continued dentin deposition
Cracked tooth from masticatory impact on the margin of the restoration
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Salivary organisms can penetrate the crack, causing inflammation, pain and eventually pulpal pathosis
Round to oval calcified masses appearing on either the canal or coronal portions of the pulp organ
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Presence of pulp stones is significant
Appear in teeth that have suffered injury as well as in otherwise normal appearing pulps
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Reduce the overall number of cells within the pulp
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Occur in unerupted as well as erupted teeth
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Noted in most pulps of permanent teeth, especially in individuals over 60 year of age
Act as impediment to debridement and enlargement of the root canal system during endodontic treatment
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FIBROSIS OF THE PULP
Removal of pulp does not affect the tooth even after many years o
Fibrous elements increase in amount but cellular elements decreases
Although the enamel of the tooth may become brittle, its function is not affected
ATROPHY OF THE PULP o
o
CLASSIFICATION OF PULP STONES/DENTICLES:
Decrease in size of the pulp due to decrease in structure contents
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RETICULAR ATROPHY
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Inflammation of the pulp can spread to the periodontium and vice versa
Pulp horns recede with age
FORMATION OF PULP STONES OR DENTICLES o
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o
PROGRESSIVE NARROWING OF PULP SPACE o
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Because they represent contact of the pulp with the periodontal tissues
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AGE CHANGES OF PULP: •
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Pulp may assume the appearance of a net
TRUE DENTICLES
o
PARALYSIS OF FUNCTION o
ACCORDING TO HISTOLOGIC STRUCTURE
Due to chronic pathological processes like deep carious lesions, pulpal abcesses, chronic cellular infiltrations
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Have dentinal tubules like dentin
FALSE DENTICLES
Concentric layers of calcified tissue
In the center bay be a group of cells that appear necrotic
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ACCORDING TO LOCATION IN RELATION TO DENTINAL WALL o
FREE DENTICLE
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Denticle completely surrounded by pulp tissue
ATTACHED DENTICLE (ADHERENT)
Denticle is partly fused to the dentinal wall
EMBEDDED DENTICLE (INTERSTITIAL)
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Serve as the nidus of denticle formation
Denticles completely surrounded by dentin
ACCORDING TO FORM o
NODULAR
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AMORPHOUS
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Round in shape
Indefinite or no determinate form
FIBRILLAR (DIFFUSE)
Elongated calcification following the course of blood vessels and nerves
Appear more often in the root canal
-Rosette Go 020709
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